Showing posts with label emotions. Show all posts
Showing posts with label emotions. Show all posts

Sunday, May 19, 2013

Jaak Panksepp and Lucy Biven, The Archaeology of Mind, Neuroevolutionary Origins of Human Emotions (2012)

At its most fundamental level, the neurosensory system of every animal, including humans, is a physiological system related to monitoring our entire physical system, whether the animal is awake or not, and, when awake (including the sleep-wake transition period), reacting to stimuli.  The latter is referred to as the arousal system.  In the case of vertebrates, four neurotransmitters (chemicals) --- acetylcholine, norepinephrine, dopamine, and serotonin --- stimulate different arousal systems originating in the brain stem, evolutionarily the oldest part of the vertebrate brain, and motivate certain behaviors such as seeking food, flight or fight behavior, and sexual activity.  There are certain emotional systems that are virtually at the core of the arousal system, at least during periods of wakefulness, and for several decades now, Jaak Panksepp has been researching and advocating that these emotional systems have their origins with animals evolutionarily older than humans, located in the older subcortical areas of mammalian brains and only later connected with the cortical areas. 

The Archaeology of Mind begins and ends with vertebrate animals, yet the evolutionary story is older, and to tell the story of what is missing from Panksepp's account I excerpt heavily from Steven Rose's The Future of the Brain, which outlines the evolution of the brain from unicellular organisms, to eukaryotes, to invertebrate animals and vertebrates.  This excerpting is important to a point I wish to make.  Rose says this:

"By the time that cells capable of metabolism and faithful replication, of symbiogenesis and competition appear, all the defining features of life have emerged:  the presence of a semi-permeable boundary separating self from non-self; the ability to metabolise -- that is, to extract energy from the environment so as to maintain this self --- and to self-repair, at least to a degree when damaged; and to reproduce copies of this self more or less faithfully.  All of these features require something we may term adaptability or behavior --- the capacity to respond to and act upon the environment in such a way as to enhance survival and replication.  At its simplest, this behavior requires neither brains nor  nervous systems, albeit a sophisticated set of chemical and structural features.  What it does require is the property that some would call a program:  at its most general way of describing both the individual chemical components of the cell and the kinetics of their interactions as the cell or living system persists through time. ***

"Built into this program must also be the possibility of modifying its expression, transiently or lastingly, in response to the changing contingencies of the external environment.  *** One way of conceiving of this capacity to vary a program is as an action plan, an 'internal representation' of the desired goal-- at its minimum, that of survival at least until replication is achieved.  I will be arguing that, in multicellular organisms, such action plans are ultimately what brains are about.

"Amongst the most basic forms of adaptive behavior drawing on such action plans is goal-directed movement-- of a unicell swimming towards food for instance. [Emphasis added].  Dip a thin capillary tube containing a solution of glucose into a drop of bacteria-rich liquid, and the bacteria collect around the mouth of the capillary from which the glucose diffuses--a phenomenon first noted as long ago as the nineteenth century.  Such simple responses engage a series of necessary steps.  First, the cell needs to be able to sense the food.  In the simplest case the food is a source of desirable chemicals --- perhaps sugars or amino acids-- although it may also be the metabolic waste products excreted by another organism.  Indeed the molecule does not have to be edible itself provided it can indicate the presence of other molecules that can be metabolized-- that is, it acts as a signal.  *** But signals are only signals if there is recipient who can interpret the message they bear.  Cell membranes are studded with proteins whose structure is adapted to enable them to trap and bind specific signaling molecules floating past them, and hence read their message.  This chemical detection system is the most basic of all sensory mechanisms.

"Interpreting the message --- using it to develop a plan of action -- should make it possible for the cell to determine the direction of the gradient and finally to move up it to the source.  Moving towards a specific chemical source --- chemotaxis --- requires that the cell possess some sort of direction indicator or compass.  One way of creating such a compass, employed by bacteria, is to swim in a jerky trajectory, enabling the cell to interpret the gradient by comparing the concentration of the attractant chemical at any moment with that a moment before.***"

If Jaak Panksepp were reading this passage he would certainly connect it to his research of emotions in animal brains.  It describes the precursor to what Panksepp regards as the most central emotional system in mammals: the SEEKING system (see below).  Rose continues:

"The molecules trapped by the receptor on the surface membrane serve as signals, but very weak ones.  To produce as dramatic a cellular response as turning and moving in the right direction requires that signals are highly amplified.  The mechanism by which this is carried out, even in the seemingly simplest of unicells turns out to be the basis on which the entire complex apparatus of nervous systems and brains is subsequently built.  The receptors are large proteins, oriented across the lipid membrane, with regions sticking out into the external environment, and also 'tails' which reach into the interior of the cell (the cytoplasm).  When the signal receptor binds to the receptor protein its effect is to force a change -- a twist, if you like -- in the complex shape of the receptor.  ***

"One way of speaking of this process, favoured by neurologist Antonio Damasio, even in so limited an animal as Paramecium, is as 'expressing an emotion.'   Emotion for Damasio, is a fundamental aspect of existing and a major driver of evolution.

"*** With multicellularity, 'behaviour' becomes a property of the organism as a whole, to which 'needs' of individual cells are subordinated.  The internal representation which makes possible the action plan for organism can be delegated to specific cell ensembles.  This requires new modes of communication to be developed.  Where previously there were only two classes of signals -- those arriving from the external environment to the cell surface, and those internal to the cell --- there are now three.  Signals from the external environment are still registered by sensory cells on the surface and are transmuted by molecular cascades with them, but now the response to those cascades requires that further messages be sent from the sensory cells to other regions of the body, including of course the contractile cells.  Sometimes the sensory cells make contact with intermediaries whose task it is to synthesise and secrete the necessary 'messenger molecules.'  [Emphasis added]. The messengers can then be distributed through the body either by way of a circulatory system or by diffusion through the extracellular space between the body cells, and are detected as before by specialized receptor proteins on the surface membranes of their targets.  When molecules that served such messenger functions were first identified in mammals, they were given the generic name of hormones.  It was only later, and to some surprise, that it was discovered that many of the same molecules also serve as intercellular signals in very early multicellular organisms, another powerful example of evolutionary conservation.***

"It is easy to imagine a sequence whereby neurons evolved from secretory cells.  Instead of discharging their contents generally into the surrounding space and circulatory system, the secretory cells could have put out feelers (called 'processes') enabling them to make direct contact with their targets so as to signal rapidly to them and them alone.  Messages could be conveyed between the two either electrically or chemically --- by a depolarizing wave or by secreting a messenger molecule across the membrane at the point where the two cells touch.  In fact, both phenomena are know to occur.

"The first step towards such nervous systems can be seen among the large group of Coelenterates, believed to be amongst the earliest true multicellular animals.  The best known is perhaps the Hydra, a tiny creature that sits at the bottom of streams attached to rocks or water plants, waving its tentacles above its mouth.   When a potential source of food brushes past its tentacles, the Hydra shoots out poisonous threads, collects the paralysed victim and thrusts it into its mouth.  *** A well fed Hydra is quiescent; when hungry it waves its tentacles vigorously, or moves its location by repeatedly turning head-over-heals, seeking food-rich or oxygen-rich environments (once again, Damasio would regard these acts 'expressing emotions').***

"What distinguishes a fully-fledged nervous system --- our own for instance --- is a one-way flow of information through the system, from dendrites to axon, from sensory cell to effector.  Of course this is mediated via all the feedback loops, but none the less there is a directionality to it that the Hydra's does not possess.

"Whereas the Hydra's neurons are scattered throughout the body, the next crucial step was to concentrate them within an organized system. *** C. elegans  has a head and tail end, and as it is more important for it to know where it is going than where it has been, many of its sensory cells are clustered at its head end.  From these, nerve connections run to clusters of interneurons, pack into groups (ganglia) with short interconnecting processes between the cells within the group and longer nerve tracts leading out along its gut and ultimately to the effectors:  contractile, egg- and sperm producing cells.  These neurons use many of the neurotransmitters that are found in mammalian brains (notably the amino acid glutamate), an indication of how far back in evolutionary terms these molecules were adapted for signaling functions.***

"The evolutionary track I have been mapping," writes Rose, "has led from proto-cells to faithfully replicating eukaryotes capable of responding adaptively to patchy environments, from single-celled eukaryotes to multicellular animals with internal signaling systems, and from these to fully-fledged nervous systems capable not merely constructing action plans, but of modifying those plans, at least temporarily, in response to environmental contingencies.  But we haven't yet arrived at brains.  This must have been the next step along the evolutionary path that led to humans.  Concentrating neurons in ganglia is a way of enhancing their interactions and hence their collective power to analyze and respond to incoming stimuli.  Locating them at the front end of the organism is the beginning of establishing not merely a nervous system but a brain, though head ganglia or brains only slowly begin to exert their primacy over the other ganglia distributed through the body.*** [Turning to invertebrates] although insect (arthropod) and molluscan neurons are pretty similar to human neurons, and the biochemical motors that drive the system -- their electrically excitable membranes and the neurotransmitters --- work in the same way, the organization of the system is entirely different.  In molluscs and arthropods the central ganglion --- the nearest any amongst these huge numbers of species have to a brain --- and the principal connecting pathways between it and other ganglia lie arranged in a ring around their guts.  This is a device that can be seen even in earthworms, and it imposes a fundamental design limitation on the complexity of the nervous system.***

"The development of large brains required two major changes in the construction of nervous systems:  the separation of the nerves themselves from the gut, and the concentration of nervous power.  It also required the first step towards the development of a bony skeleton.  Amphioxus,  small sea-floor fish, is an example.  Less behaviourally sophisticated than octopus or bee, it has a flexible rod of cartilage, a notochord, running down its back --- the forerunner of the spinal column --- with the merit of providing a bracing device against which muscles can pull.  More relevantly for the present argument is that eh major nerves and central ganglion lie in a continuous tube running the length of the creature's body, thus disentangling them from the gut and giving space for growth."

We have not even discussed Panksepp's research yet, but there is much here in Steven Rose's account of the evolutionary development of the animal nervous system that indicates the system of neurotransmitters and specialized receptors found in vertebrates long preceded the development of the brain stem in vertebrates.  And there is a suggestion by Steven Rose that this system was capable of "expressing emotions," although probably not in the same sense that Panksepp intends.  But it would be fair to say that human emotional systems and those of other mammals not only have their origins in vertebrate animals older than humans, but in the earliest forms of life on earth.  This is an anthropomorphic view of human emotions as described by Frans DeWaal in The Ape and The Sushi Master (see June 17, 2010 post).  To be sure, Panksepp is careful to admonish in his discussion of similarities between the neurological systems of humans and other mammals that "similar does not mean the same."  There are similar structures and similar transmitters and receptors in the brain, but their location within the brain may be slightly different or even vastly different, and those differences may result in small or even large differences between humans and other mammals.  But in identifying these similarities, Panksepp observes, as the book's subtitle hints, the neuroevolutionary origins of human emotions.  Panksepp decries the history of human psychological research that declined to recognize emotions in animals.  There is considerable research available today that rebuts that notion.

Panksepp discusses several emotional systems, but central to nearly all of them is what he has labeled the SEEKING system.  And in beginning this discussion, we can think back to Steven Rose's reference to the "goal-directed movement-- of a unicell swimming towards food for instance." 

Panksepp is controversial within the neuropsychiatric community, challenging some of the dogmas of neuroscience and human psychotherapy.  One of the dogmas is reflected in this statement from Rita Carter's Mapping the Mind (see November 6, 2011 post):  "A huge volume of evidence suggests that consciousness emerges from the activity of the cerebral cortex that the particular type of consciousness that includes the sense of self requires activation in the frontal lobes.  Ask yourself this:  Where, precisely, do I feel that "I" am centered?  If you are like most people, you will point to a position just above the bridge of your nose.  It is right behind here that you will find the prefrontal cortex --- the area of the frontal lobe most closely associated with the generation of consciousness.  This region is also responsible for our conscious perception of emotion and our ability to attend and focus.  Most important of all, it endows the world with meaning and our lives with a sense of purpose.  The symptoms of schizophrenia, depression, mania and Attention Deficit Disorder are mainly due to frontal lobe disorder."  Carter's sentiment reflects a view that leads psychotherapists to focus on treating the executive, regulatory capacity of the human brain in the frontal cortex in order to overcome these disorders.  While Panksepp does not dismiss the role of the prefrontal cortex in the conscious life of humans, he does disagree with the directionality implicit in this statement:  for Panksepp, like Antonio Damasio (see April 8, 2011 post) "the generation of consciousness" begins with the evolutionarily older parts of the brain --- in the midbrain, where neurotransmitters are generated  --- as well as the limbic system, which together are at the foundation of the seven emotional systems he describes in Archaeology of Mind.   It is here that the "core self" of consciousness emerges, or as Panksepp calls it, the core affective self.  The symptoms of certain mental disorders, Panksepp believes, are not "mainly due to frontal lobe disorder" but may have more to do with the imbalanced (excessive or diminished) production of specific chemicals in the brain in the more ancient parts of the brain.  And as the previous post suggests, epigenetics provide some explanation in the case of stress disorders caused by early childhood abuse leading to excessive production of cortisol that overwhelms the ability of the limbic system to restore calm. 

The seven emotional systems described by Panksepp (and he does not rule out that there may be more) are these:

The Seeking System.  This does not immediately sound like it describes an emotional system, but clearly Panksepp is correct in characterizing the Seeking System.  This is the system "that allows animals to search for, find and acquire resources that are needed for survival.  Arousal of this Seeking System produces all kinds of approach behaviors, but it also feels good in a special way.  It is not the kind of pleasure we experience when eating a fine meal, or the satisfaction we feel afterwards.  Rather it provides the kind of excited, euphoric anticipation that occurs when we look forward to eating that meal . . . the anticipation of sex . . . the thrill of exploration."  Panksepp refers to the Seeking System as the primary process emotional powers that makes animals into active agents in their environments.  "Among animals in the wild, it is easy to see the Seeking system in action.  Resources are not readily available and animals must persistently seek them out in order to survive.  They must hunt or forage for food and search for water, find twigs or dig holes to fashion sheltering nests.  The Seeking system urges them to nurture their young, to search for a sexual partner, and when animals live in social communities, to also find nonsexual companions, forming friendships and social alliances. . . Although this system vigorously responds to homeostatic needs, to emotional urges and to enticing temptations, it operates more or less continuously in the background, albeit at much lower levels when people and animals are not in any particular need of resources or troubled by problems that urgently require solutions.  This system keeps animals constantly exploring their environments so they can remember where resources are."  Importantly, in Panksepp's view, it is the Seeking System that is the motivator behind the intellectual pursuits of the neocortex:  "the neocortex does not provide its own motivation; the neocortex is activated by subcortical emotional systems . . . the neocortex is the servant of our emotional systems."  It is the Seeking System that urges architects, artists, writers, politicians, and scientists to discover new and better ways to solve problems and express themselves.  It "energizes all human creativity."  Seeking arousal "is an anticipatory gift of nature that provides seemingly infinite opportunities for learning; with the developmental/epigenetic emergence of higher mental processes, it gradually fine-tunes reasonable expectations, working hypotheses, as in the conduct of science."  It is intimately connected with learning, which Panksepp describes as an "automatic, unconscious process that enhances are natural proclivity to engage with the world in ever more subtle ways as our minds mature."  In contrast, affect (behavioral outcomes connected to arousal of instinctual emotional systems) is never unconscious; it is felt.

Chemically, the Seeking System is understood to be aroused by dopamine transmitters, but glutamate, which functions in learning and memory, and neuropeptides such as orexin and neurotensin are understood to activate the Seeking System while dynorphin is believed to deactivate it.  The neurons for these transmitters are found in the midbrain:  anatomically, ventral tegmental area, the medial forebrain bundle, the lateral hypothalamus, the nucleus accumbens, and then running to the medial prefrontal cortex via the mesolimbic and mesocortical dopamine pathways.  "In all mammals," notes Panksepp, "the nucleus accumbens interacts with the medial frontal cortex to promote simple appetitive learning (and addictions).  Because the Seeking System energizes the frontal neocortical regions, especially the medial zones that focus on immediate emotional needs, we are able to devise strategies to obtain rewards and escape sanctions (pain) and other pitfalls.  We remember particularly pleasurable experiences and the possibility of addiction is created.  Dopamine transmitters are associated with drugs of abuse, and when they are overly excited there can be negative consequences from addiction.  On the other hand, when the Seeking System is underactive, depressive feelings can emerge. Humans differ from other animals here in one important respect; the dopamine pathways that energize the cortex are linked not only to the frontal cortex but to other sensory-perceptual cortices in the back of the brain.

The Rage System.  The Rage System needs little explanation:  the foundation of anger and aggression.  What it is not deserves some explanation:  it probably has little to do with war among societies (group aggression), nor is it about predatory aggression such as seeking food.  In contrast to the Seeking System, which is largely a "positive" emotion, the Rage System produces unpleasant affects.  The Rage System is connected to dominance systems in species.  The Rage System runs from the medial areas of the amygdala to the medial hypothalamus to areas of the periaqueductal gray (PAG). As with the Seeking System (and all the other emotional systems Panksepp describes), these are the ancient areas of the brain.  The chemicals that can promote rage include testosterone (known to promote physical aggression in males to a greater extent than females), Substance P (important to pain perception), norepinephrine, glutamate, acetylcholine, and nitric oxide synthases.  The Rage System can be controlled by chemical inhibitors such as gamma-aminobutyric acid (GABA) and oxytocin. 

The Fear System.  Similarly, the Fear System needs little explanation.  Like the Rage System, it is not a positive emotion; it produces anxiety, stimulates flight, fight or freezing.  The Fear System operates between the PAG and the amygdala and it is aroused by external and internal stimuli, notably pain, but some responses appear to be innate caused by hard-wired sensory inputs.  Panksepp mentions rats fear of open spaces, sudden movements and loud noises as example innate fear responses.  But fear is connected to memory as well, and memory plays a significant role in conditioning fear responses.  On memory, Panksepp explains, that learning and memory are automatic and involuntary responses (mediated by unconscious mechanisms of the brain), which in their most lasting forms are commonly tethered to emotional arousal. Emotional arousal is a necessary condition for the creation of fear-learning memories.

The Lust System. The Lust System drives basic mammalian physical impulses (sexual affects) on the one hand and social emotions on the other, which can be both positive and negative.  It can drive anti-social behavior (rape, stalking) as well as building families and promoting other forms of well-being.  In the male brain the center of primary sexual urges is in the medial regions of the anterior hypothalamus, (although Panksepp notes that "the precise brain location varies from one species to another).  Testosterone stimulates pleasure in the male, which activates neuropeptides such as vasopressin and promotes sexual ardor, courtship, intermale aggression and possibly jealousy.  Testosterone also activates nitric oxide in the brain, which promotes heightened sexual eagerness.    In females, estrogen and progesterone (the estrus cycle) controls sexual arousal, but adrenal testosterone plays a role in sexual receptivity.  The Lust System, Panksepp says, "recruits" the Seeking System "dopamine-fueled search for companionship.

The Care System.  The Care System is not universal in the animal kingdom, but nearly all mammals and birds exhibit maternal care for their young.  In fish, the job of tending to a nest of eggs is left to fathers, and the brain circuits that drive this behavior Panksepp calls the Care System.  Panksepp notes that researchers learned of the existence of the Care System in mammals when they discovered that blood transfusions from postpartum female rats to virgin rats would lead to maternal behavior in the virgin rats, including nest building, hovering over young, and gathering the young who strayed from the nest.  Panksepp concedes that researchers still do not which chemicals in the transferred blood interact in the brains of virgin rats to cause these behaviors, but given similarities between the urge to provide Care and the urges underlying the Seeking System, brain arousal from dopamine in conjunction with opioids, as well as oxytocin and prolactin are likely involved.  Panksepp hypothesizes that the evolution of the Care System might be traced back to chemicals found in the Lust circuits of reptiles, such as vasotocin, which has a calming effect and promotes nurturant moods in some birds, and neuropeptides like mesotocin that may have evolved in vasopressin and oxytocin, which is recognized as a key maternal chemical.  The maternal (and paternal) nurturing behavior must be recognized as a critical factor in the development of social brain systems.  Research shows that both oxytocin and vasopressin strengthen social memories and are believed to be promote social bonds among mammals.  (See July 16, 2010 post).

Research on the Care System in rats also reveals evidence of epigenetic changes leading to more prosocial behavior.  Female rats lick their pups during early development and this has been shown to influence the emotional abilities of young rats later in life.  Abundantly licked rats grow up to be less anxious, more resistant to stress, and more capable of exhibiting learning and other adaptive behavior later in life.  These adult rats have diminished stress hormones (corticotrophin-releasing factor (CRF)) and adrenocorticotrophic hormone (ACTH), more GABA receptor cites, which promotes reduced anxiety, and more receptors for glutamate and norepinephrine, which facilitate learning.  Emotionally, these animals are less anxious, showing more activity and fearlessness, and better learning and performance in a variety of fear-inducing situations.  This research could have been cited by Nessa Carey in The Epigenetic Revolution.  (See April 28, 2013 post). 

The Panic/Grief System.  Panic and grief intuitively seem like strange bedfellows but the common emotional/behavioral link in this "system" is separation anxiety, something that is seen across a number of species.  Grief connotes a sadness that arises from social loss; panic connotes a separation from a secure or stable environment.  Immediately, one can conjure linkages between what Panksepp labels the Panic/Grief System and the Care System, the Fear System.  The Panic System is seen in early childhood development over anxiety in separation of mother and child ("Born to Cry" is the title of this chapter), but it has also been found to be less active in adults.  The Panic/Grief circuits are found in several of the same subcortical areas identified with other systems, including the PAG and surrounding subcortical regions including the dorsomedial thalamus, the ventral septial area, the dorsal preoptic area and the bed nucleus of stria terminalis.  Previously identified stress neuropeptides such as CRF and  ACTH, and glutamate (an excitatory neurotransmitter associated with every emotional response) arouse the Grief System.  Imbalances in the Grief System are a key factor in a variety of emotional disorders because so much mental illness, Panksepp notes, is rooted in the incapacity to enjoy the security of warm interpersonal attachments.  Panic attacks, depression, autism, and a variety of other social phobias are part of the Grief pathologies.  The identification of neuropeptides that actually diminish separation distress and mediate the Care System, such as oxytocin and prolactin,and the stimulation of mu-opioid receptors in the brain may have role in treatments of these disorders.

The Play System.  Finally, but not least, something that one might not think of as an emotional system, but Panksepp clearly documents that it is, particularly in mammals: the Play System.  "Physical playfulness is a birthright of every young mammal and perhaps of many other animals as well. . . It is now certain that a genetically determined Play network that mediates positive affect exists in mammalian brains, although many details remain to be worked out."  The Play System is likewise concentrated in subcortical brain regions, intimately linked to the Seeking System: the urge to play is like a type of hunger, and is not necessarily a social need, although it is linked to social emotional systems. Play is linked to the capacity to laugh, a positive emotional affect. Laughter is not merely found in humans, but also noises made by rats, chirping of birds.  Laughter is stimulated early in children, including mimicry.  Like the Seeking System, dopamine, which is engaged during activity that entails considerable positive anticipation and euphoria, is believed to fuel the Play System because it is aroused (correlated) during play.  Play activates sensory inputs, such as touch, which go directly to older midline regions of the brain such as the parafascicular complex and the posterior dorsomedial thalamic regions. 

In the foregoing, I have catalogued for each of Panksepp's seven emotional systems of the brain the suspected chemistries and at the outset I tried to demonstrate that research documents the ancient role of chemicals in the neurological systems of species and their potential link to the development of emotional system.  My objective in this outline is to highlight a point in a previous post about social emotions, including moral emotions.  In his book Moral Origins, Christopher Boehm concludes by saying that in a few generations we "may have identified some of the genetic mechanisms that help us to behave egoistically, nepotistically, and altruistically, along with others that make for sympathetic generosity, domination and submission, and a variety of other socially significant behaviors that are relevant to morality, including our shame responses."  The earlier post (see November 21, 2012 post) observed that "Boehm may well be right that we will identify the genetic mechanisms behind moral and immoral behavior in a few generations, but the roadmap of investigation is already before us and it begins with emotions.  I say this for two reasons:  first, if anything, genes code for our body chemistry; genes may or may not code for specific behavior (moral or otherwise), although I doubt it (see November 30, 2009 post).  But emotions are driven by electro-chemical actions and reactions in our various body systems and ultimately the neurological system leading to our brains, and genes do code for these electro-chemical actions and reactions and genes code for our brain and other body organs.  If we want to understand the genetic basis for moral and immoral behavior we will look for the genes tied to these body systems and the chemistry that drives emotions."   Panksepp's aggregation of the research on these primary process emotions is a good peek into the links between genes, chemistries, and anatomical structures related to emotions.  In addition to linking genes with the chemicals and brain structures that drive these emotional systems, the inquiry contemplated by Boehm would presumably link these seven emotional systems to other more complex emotional systems not considered "primary process" systems,  including the social emotions discussed in the November 21, 2012 post such as embarrassment, shame, guilt, contempt, indignation, sympathy, compassion, awe, gratitude, and pride. 

One cannot help read The Archaeology of Mind without feeling that Panksepp believes he has been walking in the wilderness of neuroscientific research that treats emotional systems as fundamental, more fundamental than research of the neocortex.  While he now believes that Antonio Damasio has joined his crusade with the publication of Self Comes to Mind (see April 8, 2011 post), in which Damasio gave a tip of the hat to Panksepp's research, Panksepp is skeptical of Damasio's earlier somatic marker hypothesis and the assertion that core consciousness (a higher order mapping process outside the subcortical regions) generates inner emotional feelings of what is happening by synthesizing information from maps abut the body and about the environment. As stated earlier, it is the subcortical emotional system that energizes the neocortex, says Panksepp, not the other way around.  Fundamentally, Panksepp believes that mental and emotional disorders go hand in hand and are best understood as a chemical problem, and when understood in that leads to two important conclusions:  (1) that chemistry will have a key role in providing treatment, and (2) it will cause psychotherapists to recognize that treatment must deal with the emotional aspects of the older subcortical parts of the brain.  For Panksepp, the key question for all neuroscientists and biological psychiatrists is this:  "How are raw affective experiences created in the brain?"  The answer he believes will clarify the foundational nature of experience in general as well as affective disturbances.  For example, Panksepp writes, for depression he would ask:  Why does depression feel so bad?  Why does depression hurt?  Why is it so psychologically painful?  What does it mean to experience social pain?  Few neuroscientists have been willing to ask these questions.

One cannot conclude a statement about Panksepp's research without noting what he neither ignores, but nonetheless does not dwell on: the role of the cortical areas of the brain in human consciousness.  When he does acknowledge higher order BrainMind structures, he says this:  "Although arousals of the primary process emotional networks of mammalian brains are intensely experienced by humans and other animals, it is especially important to recognize that the secondary processes of the BrainMind, the basic forms of learning, memory, and habit formation are among the most unconscious 'mental' processes of them all.  Once we understand this, then many of the bizarre and faulty views from psychology's past may be rectified.  For instance, 'free will' is not a figment of our imagination as too many scientists are ready to claim these days.  Free will is a higher tertiary-level neurocognitive function that we use on a regular basis (and quite effectively when we are not too emotionally aroused) for future planning actions.  This is brought out beautifully in the concept of 'autonomy' and 'self-determination' as developed by Ryan and Deci (2006).  However, we cannot readily will ourselves out of underlying emotional turmoil that has been created through the consolidation of maladaptive affective patterns at primary and secondary levels of BrainMind organization.  At primary-process levels of emotional processing there is no free will, there is no 'controlled cognitions.' Neither do the automatic secondary processes of learning and memory functions, that are molded by our wild animal passions developmentally, exhibit free will.  That can only emerge from well-sculpted, deeply reflective, cognitive attitudes."  He adds, "It is surely our vast cerebral 'thinking cap' --- our extensive cortico-cognitive apparatus --- that distinguishes us mentally from our animal ancestors.  That adds layers of complexity that cannot be readily addressed with animal models."  Michael Gazzaniga would agree.  (See September 27, 2009 post). But "language," Panksepp says," our most unique cerebral skill, "emerges through emotional guidance.  Through language, however, we can uniquely study the extended tertiary-process cognitive affective consciousness of humans.  And this is why there continues to be enormous growth in descriptive (ie. nonneuroscientific) emotion studies in psychology (Davidson et all., 2003)." 

And with that paragraph, I pull the next book off of The Bookshelf. 

Saturday, December 10, 2011

Rebecca Skloot, The Immortal Life of Henrietta Lacks (2010)

The Immortal Life of Henrietta Lacks reports about a significant development in medical research that occurred during the 1950s and continues to provide benefits for both research and therapy for decades thereafter. If that was the tag line about this book, it might never had ended up on the best-seller lists. Add to that tag line that the book confronts a thorny question of medical ethics --- what sorts of disclosures must be made by medical researchers who take body tissue (in this case, cancer cells from a dying patient), and the fact that those in the medical research supply chain subsequently earn millions of dollars from that body tissue, and perhaps some in the public begin to pay attention. And add to that stew the fact that the donor was a poor African-American woman whose heirs never benefited from her donation; whose descendants suffered anxiety and some level of anger because of misinformation and ignorance when their mother's name and contribution to medical science became public knowledge two decades after she died; whose descendants never sought financial compensation or benefits, only recognition for their mother's contribution to medical science, and you have a best-selling page-turner. While there are several protagonists in this story --- including the author --- the primary protagonist are the so-called "HeLa" cells taken from the cervix of Henrietta Lacks by a doctor at Johns Hopkins University. The HeLa cells were the first "immortal" human cells ever grown in culture --- cells that reproduced themselves prolifically. They were essential to developing the polio vaccine, as well as other scientific landmarks since then have used her cells, including cloning, gene mapping and in vitro fertilization. The significance of these cells is that because they created a virtual pipeline of human cells that could be replicated in the billions, they enabled medical research to be undertaken on actual human cells, rather than on humans themselves or some other animal.

So that is the story. But there is a subliminal story that leads me back to the subject of the previous post --- the subject of identity, specifically group identity. Rebecca Skloot, the author of The Immortal Life of Henrietta Lacks, does not explore the subject of cultural identity or racial identity, but she does explore, at least superficially through her narrative, group identity in the context of a family and the family members' genetic links to their past. Genetic identity is linked to various other forms of group or social identity: political identity (the heritability of power), ethnic identity, religious identity, family identity, racial identity, and caste. But as an article in the British Medical Journal notes, "These identities overlap in various ways, and genetic evidence will not affect them all equally . . . confusion looms when genetic markers conflict with other kinds of markers of group membership such as shared culture or historical narrative." This was a point I was making in the previous post, when I pointed out that Jews do not appear to define Jewish identity strictly in terms of a genetic link to the past. It may be, as genetic research on some Jewish communities suggests, that within some ethnic/religious groups genetic identity is stronger than other groups, but is this an attribute that anyone, Jewish or not, seriously wants to promote about what it really means to be part of a human subgroup? It smacks of Nazism.

As I read Skloot's story of Henrietta Lacks and her family and thought further about The Finkler Question, I was reminded of a Hebrew word, mizpah, which means an emotional bond between people who are separated (either physically or by death). The word might have application, for example, to Jews physically separated from one another by virtue of the diaspora and their mutual recognition of a shared Jewish identity. But it would also have application to Henrietta Lacks and her children and even the grandchildren that she never knew. This bond is a type of identity, and at its core is human emotion. Several books that have been discussed in this blog have highlighted the importance of emotion in building social relations. (See April 11, 2011 post, discussing David Hume and Antonio Damasio) As Dacher Keltner writes, "Emotions are involuntary commitment devices that bind us to one another in long-term, mutually beneficial relationships." (See July 16, 2010 post). In the human context, certainly emotional bonding among the persons is an attribute of group identity, although the strength of this attribute may vary among the persons. As Frans DeWaal observes, however, this same emotional bonding may exist in some other species as well (see November 9, 2010 post).

Genetic identity is, of course, nearly definitive in the discussion of group identity at the species level, but within a species, different groups become influenced by nurture and culture and social constructs are developed. And while genes may be at the foundation of our physical design that triggers various emotions and behaviors that make us more or less social, nurture and culture are at the foundation of reinforcing and making some emotional social bonds stronger than others leading to the formation of social groups and their identity.

The tug of genetic identity is felt by Henrietta Lacks' daughter, Deborah, whose anxiety grows after she learns that her mother's cells have become famous. One of her fears is that the cancer that killed her mother might take her life as well, a fear which is quelled only when she learns that her mother's cervical cancer was caused not by a genetic disease or predisposition, but the human papillomavirus. Research indicates that individuals struggle with their genetic identity, but for reasons that appear to be related to the difficulty of many in understanding just what it is about genes that is important enough to focus upon in terms of identity. More significantly, it is an emotional bond that establishes this family identity, a bond developed during the early years' of nurturing Henrietta's children, and a shared historical narrative that ties mother and children together --- a narrative that Rebecca Skloot has told well.

Sunday, February 27, 2011

David Hume, A Treatise of Human Nature (1739)

Even for those of us who are not professional scholars, there is value in reading the original words of someone like David Hume rather than reading only what others have said about him. Part of that value is found simply in the exercise of mentally transporting yourself back in time to better understand the 18th century period in which he lived and how new ideas were being debated at that time. Another part of that value will be retrieved the next time I read about David Hume, and a greater appreciation of the point the author is making. Among Enlightenment philosophers, I chose Hume because he is too frequently cited in the books I read to not pay attention to him.

Hume, I have surmised, is regrettably overlooked by Americans in their surveys of philosophy. Other Enlightenment philosophers --- notably John Locke --- garner more attention because they were sources of inspiration for the development of American political and legal traditions. Locke is associated with the idea of "natural rights" and declared truths "we hold to be self-evident." In the field of epistemology, Locke probably receives more attention than Hume in surveys of philosophy because he was an earlier proponent of empiricism, which emphasizes the role of experience and the senses in our understanding of objects in the world over the view that knowledge is innate. Within the community of contemporary philosophers of the mind as well as psychologists and neuroscientists, Hume has received his credit for his contribution to our understanding of how the mind works --- even more so than Locke --- and that would suggest that survey courses in philosophy might reorient their Enlightenment-era discussions of knowledge and the mind to pay more attention to Hume to better appreciate how our understanding of the mind has evolved since the 18th century.

A Treatise of Human Nature is an 18th century version of How The Mind Works. It advances the concept of associationism, a concept which dominated psychology in the 19th and early 20th centuries, in greater detail than anyone had previously discussed. What Hume did not have at his disposal in the 1730s was a body of empirical research from the fields of psychology, biology, and neuroscience to inform his inquiry into human nature. He had the works of philosophers who preceded him, which he had digested prior to embarking on his Treatise, and his own series of what he called "experiments" --- introspective thinking about how his own mind and body worked and thinking about others to assess whether he could generalize from his own experience. For this reason, the Treatise carries the subtitle "Being an Attempt to Introduce the Experimental Method of Reasoning Into Moral Subjects."

Hume is an example of John Searle's Enlightenment-era philosopher trying "to cope with the problem of skepticism." (See previous January 21, 2011 post). "As to those impressions," Hume writes, "which arise from the senses, their ultimate cause is, in my opinion, perfectly inexplicable by human reason, and 'twill always be impossible to decide with certainty, whether they arise immediately from the object or a produced by the creative power of the mind, or are derived from the author of our being." In other words, the representations of things in our mind come from our sense experiences and we can never know with certainty that the object of our mind's attention produces that impression or whether it is a priori in our minds because of the act of a deity ("the author of our being."). The Treatise represents Hume's effort to "cope" with this inability to know anything directly with certainty, and he determines that the mind's ability to associate ideas enables it to make inferences that form the basis of our knowledge about external objects to which our senses are exposed. The three principle qualities that enable the mind to associate or connect various ideas are resemblance, contiguity (in time and space), and cause and effect.

In his book Mind, John Searle writes that "most philosophers will agree [that Hume's account of causation] is one of the most impressive pieces of philosophical prose ever written in the English language." Why does he say this? Because Hume reasoned a way in which we can generalize about reality from specific sense experiences. Hume describes a principle of causation and a principle of causality, which are not the same. The first says every effect has a cause; the second says that like effects have like causes. We experience something through sensation, but the only quality from that single experience is one of contiguity (before and after, or next to), but we do not necessarily make a connection between that that single experience and what caused it without a constant repetition of similar experiences (resemblances). The greater the regularity of those similar experiences produces a "felt determination of the mind" on which a generality is based. Hume notes that probability plays a role here in creating Belief. "Should it be demanded why men form general rules, and allow them to influence their judgment, even contrary to present observation and experience, I should reply, that in my opinion it proceeds from those very principles, on which all judgments concerning causes and effects depend. Our judgments concerning cause and effect are derived from habit and experience; and when we have been accustomed to see one object united to another, our imagination passes from the first to the second, by a natural transition, which precedes reflection [that is before we even seriously think about what we just experienced] and which cannot be prevented by it." It is what Searle calls "Hume's regularity theory of causation" that has been influential in the philosophy of the mind.

One can be critical of Hume, because he does not believe that we actually experience necessary connections between things (causation), or that we actually experience our conscious selves and are forced to rely on frequently repeating, resembling events that strengthen the force of our perceptions before we can form "beliefs" about external objects or our identity, without having to disparage his analysis of how the mind works. Hume's account of human nature integrates sensation, feelings, emotions, and memory --- what today we recognize as the neurobiological network of the human body, including the brain, that constitutes a conscious human agent. "Belief," says Hume, "is more properly an act of the sensitive, than the cogitative part of our natures."

This book is intended to be a treatise on the nature of humans, but Hume consciously ducks discussing human biology: "The examination of our sensations belongs more to the anatomists and natural philosophers [scientists] than to moral; and therefore shall not at present be entered upon." And even if he had not avoided the biology of what makes us human, today's reader would have learned little in light of the fact that Hume did not enjoy what John Searle notes that we enjoy in the 21st century: "a huge accumulation of knowledge [about biological systems, biological evolution, DNA and reproduction, embryology, etc.], which is certain, objective, and universal." (See previous post of January 21, 2011). But the absence of that knowledge from Hume's treatise should not cause one not to marvel at the depth of his introspection on human nature.

It is important to give Hume credit for recognizing the role of feelings and, what he calls "passions" in human nature and human decision-making. Sensations (experience) give rise to passions (reflective impressions). Sensations are either pleasurable (good) or painful (evil,bad), with varying degrees of each known to us. Certain passions are associated with pleasure (e.g., pride, love, benevolence, compassion, hope, joy), other passions are associated with pain (e.g., humility, hate, anger, malice, envy, fear, grief). The different passions vary by degree, which Hume labels "violent" or "calm." Like knowledge, passions are stronger or weaker because of repetition in our experience and the extent to which those experience become embraced by custom [culture]. Reason, says Hume, is not some objective, fully-informed distinct mental state separate from the passions; it is nothing more than a popular term for the "calm" passions, reflecting Hume's view that reason is never isolated from our emotions that are derived from our experience (sensations). Understood in this light, Hume foreshadows the tradition of Williams James that continues today in the works of Antonio Damasio (The Feeling of What Happens), which recognizes that emotions and feelings are caused by physiological changes attributable to electro-chemical stimuli in the neurobiological system.

The modern reader of the philosophy of mind, psychology, biology, and neuroscience will recognize that Hume identified and seized on human attributes and behavior that are now more completely understood in biological terms. For example, Hume's statement that "The mind is a kind of theatre, where several perceptions successively make their appearance; pass, re-pass, glide away, and mingle in an infinite variety of postures and situations" reminds one of Damasio's reference to consciousness as a 'movie within a movie.' The difference between Hume and contemporaries such as Damasio is revealed in Hume's statement: "The comparison to the theatre must not mislead us. They are the successive perceptions only, that constitute the mind; nor have we the most distant notion of the place, where these scenes are represented, or of the materials, of which it is composed." For Damasio and his peers, while we may not have a full account of the mind and brain, we no longer have a "distant notion" of the place where and how images are represented in the brain and we have a very good of the physical attributes of which the brain is composed.

Hume even foreshadows our modern discussion of mirror neurons when he writes that "the minds of men are mirrors to one another, not only because they reflect each other's emotions, but also because those rays of passions, sentiments and opinions may be often reverberated, and may decay away by insensible degrees," and he connects this observation to human empathy and sympathy for fellow humans. Later, in Book 3, Hume writes, "When I see the effects of passion in the voice and gesture of any person, my mind immediately passes from these effects to their causes, and forms such a lively idea of the passion, as is presently converted into the passion itself. In like manner, when I perceive the causes of any emotion, my mind is conveyed to the effects, and it is actuated with a like emotion." In statements like this one senses a primitive Enlightenment precursor to the research of Marco Iacoboni and others as described in Mirroring People: The Science of Empathy and How We Connect. (See September 18, 2009 post).

The Treatise does not end with Hume's conclusion about the nature of the human mind and how sensory perceptions connect to feelings and emotions that become experiences, memories, and ultimately beliefs about the external world and free-will, but the Treatise expands to include the construction of a cultural reality and social institutions for the regulation of human behavior (customs, rules, and law). Hume is not a social contractarian in the tradition of Hobbes, Rousseau (and later, Rawls). Morality and social structure do not evolve from human reason: "morality is more properly felt than judged," indicating that justice is derived from our impressions, not from reason. The passion sympathy [empathy] is the chief source of our moral distinctions, says Hume. Consistent with Hume's "system" of the human understanding that is described in Book 1, our sensory experiences of pleasure and pain give rise to positive and negative passions, which in turns leads to a propensity toward something that is favored (in the case of positive passions) or an aversion from something that is disfavored (in the case of negative passions). In either case, we are talking about self-interest and self-interest includes a recognition that reciprocal relations with other humans (including promise-making behavior) leads to a moral sense of virtue (favored) and vice (disfavored). After awhile, humans develop a general "sense" of common interest. This leads to the development of social rules, laws, and institutions to enforce them. This process is not the outcome of a rational bargain and a signed contract, but it is a process that reflects an evolving tendency toward stasis, much as the human body pits the positive and negative passions that tend toward homeostasis.

We can also recognize in the Treatise a primitive discussion of whether altruistic acts are confined to biological relations (kin) or are capable of being expanded to wider societal relations and nations. Hume writes, "When experience has once given us a competent knowledge of human affairs and has taught us the proportion they bear to human passion, we perceive that the generosity of men is very limited, and that it seldom extends beyond their friends and family, or, at most, beyond their native country." This same sentiment is debated today in Holldobler and Wilson's The Superorganism (see November 4, 2009), Oren Harman's The Price of Altruism (see October 13, 2010 post), and Frans DeWaal's The Age of Empathy (see November 9, 2010 post).

Hume clearly disputes Bernard Mandeville's view that man is driven by egotistical impulses, seeking self-preservation and advancement. (See January 30, 2010 post). Hume does not deny egotistical impulses and the pursuit of self-preservation, but for every passion that Hume identifies there is a counter-passion: in the case of self-interest, there is sympathy and empathy for others. In Mandeville's view, it is societal institutions that regulate and restrain man's self-seeking drives; in Hume's vision, sympathy, empathy, generosity, and reciprocal behavior are part of human nature. Hume's assessment of human nature has clearly prevailed from the modern view of biology, psychology, and neuroscience. In this regard, Hume is closer to his fellow Scotsman, Adam Smith, whose Theory of Moral Sentiments is at the core of Amartya Sen's The Idea of Justice (see January 11, 2011 post).

Nearly four centuries after Hume wrote his Treatise, we recognize that his observations on human nature are not all that far from those which science and experiment confirm for us today. Associationism may no longer hold sway in our view of how the mind works, but the linkage between sensations, feelings, emotions, reflection, and reasoning, which Hume describes in the Treatise, is the same linkage that neuroscientists describe today. The limitation of the treatise, which I think we will appreciate from the next book off The Bookshelf by Antonio Damasio, is that Hume did not fully appreciate how we construct a personal identity for ourselves. Hume says, "The identity, which we ascribe to the mind of man, is only a fictitious one, and of a like with that which we ascribe to vegetables and animal bodies. It cannot, therefore, have a different origin, but must proceed from a like operation of the imagination upon like objects." In other words, Hume says that we come to know our self in the same way we come to know external objects. Presumably this means Hume is coping with his skepticism over his own identity just as much he is coping with his skepticism toward the broccoli he ate for dinner. Let's see what Damasio has to say.

Friday, July 16, 2010

Dacher Keltner, Born To Be Good: The Science of a Meaningful Life (2009)

When I first saw Born to Be Good at the store in a display of books, the title nearly turned me off. It sounded like a self-improvement book, a genre I generally avoid. But the subtitle caught my attention. It suggested that this was a scientific presentation, so I flipped the pages and saw references to Paul Ekman's work on facial expressions --- research that I had heard of, but never read --- along with references to Darwin, Frans DeWaal, and even the musician Steve Reich. And the author Dacher Keltner, a name that I was unfamiliar with, is a professor of psychology at my alma mater, the University of California, so I took a chance. I was not disappointed, notwithstanding the kitschy references to jen and the jen ratio, a Confucian measure of one's happiness.

Born to Be Good is in the genre of scientific literature about what it means to be human, so it fits with Michael Gazzaniga's Human (September 27, 2009 post), Marco Iacoboni's Mirroring People (September 18, 2009 post), and Marc Hauser's Moral Minds, all which document the social, cooperative, and even altruistic nature of the human species and the evolutionary origins of cooperation and altruism within our very social species. If there was a study in contrasts to read after Richard Wrangham's Demonic Males (July 1, 2010 post) about the dark, violent side of human nature, Born to Be Good is it. Keltner even stole a chapter title from Frans DeWaal's The Ape and The Sushi Master (June 17, 2010 post) and titled one of his chapters "Survival of the Kindest." Moreover, Born to Be Good fits in the lineage of research represented by Antonio Damassio's The Feeling of What Happens, which documents the fundamental role of emotion in human decision-making.

"Emotions are involuntary commitment devices that bind us to one another in long-term, mutually beneficial relationships," Keltner says. Emotions are communicated through several sensory means: visually through facial expressions, which Keltner documents based on his own research and that of his teacher and mentor, Paul Ekman, explaining how muscles in the face are linked to and controlled by neural pathways in the brain that make them reliable indicators of emotion. In facial expression, we recognize embarrassment, which signals our moral sense of wrongdoing and respect for the judgment of others. In facial expression, the smile signals friendly intent and affection among peers and movement toward cooperation and intimacy. In facial expression, laughter triggers mirror neurons in the brains of others that builds cooperative bonds between one who laughs and the other who hears the laugh. Keltner tells us that teasing is not the same as bullying, and is a type of playful communication designed to ferret out another's commitments that bolsters social life. Emotions are communicated through touch, and the skin, our largest sensory organ, evolved to be an important part of social communication among humans and their predecessors.

Keltner is at his best when he discussed the evolutionary origins of love (trust) and compassion and evolutionary development of the vagus nerve, which releases a hormone, oxytocin, that is linked to feelings of sympathy, concern over the vulnerability of others, and caregiving, and which can be stimulated by touch, and is linked to monogamy in certain species. "We have neuropeptides that enable trust and devotion, and a branch of nerves that connects the brain, the voice, and the heart that enables caretaking," says Keltner. "We are wired for good." The other books cited above bear this out, based on other research as well. But still, the dark side of human social behavior documented by Wrangham should not be forgotten as we experience awe for others and even nature writ large. Wrangham makes his case that violence might be important to survival in some primates, although he considers that it could be fatal to the survival of humans.

But Keltner makes the other case --- that love, compassion, are caregiving cooperation.

The big idea here is how information is communicated and the capabilities of the human mind. And again, as in the books discussed in several prior posts, it is information at a chemical level that is a key form of communication. "The profound vulnerability of our big-brained offspring wired us into an instinct to care. It created in us a biologically based capacity for sympathy. It produced a vagus nerve, loaded up with oxytocin receptors, the provenance of feelings of devotion, sacrifice, and trust. It yielded a rich set of signals --- empathetic sighs, oblique eyebrows, and soothing touch, which trigger vagus nerve response and oxytocin and opioid release in the recipient, giving rise to oceanic feelings of connection."